Pearl millet (Pennisetum glaucum) restorer lines for breeding dual-purpose hybrids adapted to arid environments

Abstract

The adoption of pearl millet hybrids in the north-western arid zone has been very limited in contrast to their widespread coverage in relatively more favourable areas. This research was conducted to assess the combining ability of progenies derived from a composite, called Mandor Restorer Composite (MRC) that was synthesized using 12 lines with inbuilt combination of characters that are useful for arid environments. Testcross hybrids of 43 MRC progenies made on five diverse male-sterile lines were evaluated for their performance in four environments over three years (2005-07) under rainfed conditions of arid zone. There existed significant and exploitable differences among restorer (R) lines in their combining ability for biomass, grain yield, stover yield, harvest index and panicle harvest index under receding moisture conditions. General combining ability (GCA) for early flowering was consistently and positively related to GCA for grain yield. GCA for harvest index was positively and significantly related to GCA for grain yield, but was variably negatively related to stover yield. Neither GCA for HI nor GCA for time to flowering had as large an effect on GCA for grain and stover yields as did GCA for biomass. The results suggested that GCA for earliness, biomass and HI are not necessarily mutually antagonistic characteristics under arid zone conditions indicating that there are good prospects of identifying lines to produce hybrids with enhanced grain and stover yields without compromising crop duration. This study also identified a few progenies that had significant GCA for grain and stover yield in early-maturity background.